Diagnostic performance of magnetic resonance imaging-targeted biopsy for PI-RADS ≥3 peripheral zone lesions in multiparametric prostate magnetic resonance imaging: correlation with clinically significant prostate cancer

PURPOSE: To evaluate magnetic resonance imaging (MRI)-targeted biopsy (MRI-TB) performance in detecting clinically significant prostate cancer (csPCa) with a Prostate Imaging Reporting and Data System (PI-RADS) score of ≥3 peripheral zone (PZ) lesions using multiparametric MRI (mpMRI)-histopathology correlation. METHODS: This retrospective study included 141 patients with 187 PZ lesions who underwent mpMRI followed by both MRI-TB and transrectal ultrasound-guided systematic biopsy (SB) between December 2021 and December 2024. All mpMRI scans were evaluated by a board-certified experienced radiologist in accordance with the PI-RADS version 2.1 criteria. The csPCa detection rates of SB, MRI-TB, and combined biopsy (CB) were compared. Statistical analyses included McNemar’s test, Fisher’s exact test, and the Mann–Whitney U test. A P value <0.05 was considered statistically significant. RESULTS: Among the 141 patients (187 PI-RADS ≥3 PZ lesions), patients with csPCa exhibited significantly higher prostate-specific antigen (PSA) levels (15.3 vs. 8.2 ng/mL; P = 0.02), lower prostate volume (52.4 vs. 78.6 mL; P < 0.001), and three-fold higher PSA density (PSAD) (0.30 vs. 0.10 ng/mL/mL; P < 0.001) than non-csPCa cases. Notably, PSAD > 0.15 ng/mL/mL occurred in 78% of patients with csPCa vs. 18% in non-csPCa cases (P < 0.001). Moreover, MRI-TB detected significantly more csPCa than SB (17.7% vs. 10.7% of lesions; P < 0.001), with maximal advantage in PI-RADS 4 lesions (20.7% vs. 10.9%; P = 0.004). By contrast, CB did not significantly increase csPCa detection over MRI-TB alone (19.8% vs. 17.7%; P = 0.125). Chronic prostatitis (CP) (34.0% of benign cases) confounded PI-RADS specificity. CONCLUSION: For csPCa detection in PI-RADS ≥3 PZ lesions, particularly PI-RADS 4, MRI-TB outperforms SB. For PI-RADS 5, SB and MRI-TB showed equivalent efficacy. However, MRI-TB alone suffices for PI-RADS ≥4 lesions or PSAD >0.15 ng/mL/mL, whereas CB remains preferable for PI-RADS 3. The high CP prevalence underscores the need for adjunctive biomarkers to improve specificity. CLINICAL SIGNIFICANCE: MRI-TB optimizes csPCa detection for PI-RADS ≥4 PZ lesions, reducing reliance on SBs. A PSAD threshold >0.15 ng/mL/mL effectively stratifies biopsy necessity, and high CP prevalence (34% of benign cases) underscores the need for adjunct biomarkers to improve specificity in PI-RADS 3–4 lesions.